Ways of studying the brain

Question 1

How does functional magnetic resonance imaging work? (fMRI)

Answer 1

• Detects changes in both blood oxygenation and flow that occurs as a result of neural activity in specific parts of the brain when performing a task
• researchers detect which areas are rich in oxygen thus active

Question 2

What are the strengths of fMRI’s?

Answer 2

• does not rely on use of radiation
• if administered correctly it is virtually risk free non-invasive/straightforward to use
• produces images that have high spatial resolution (1mm) clear picture of how brain activity is localized

Question 3

What are the limitation of fMRI’s?

Answer 3

• expensive compared to other neuroimaging techniques
• poor temporal resolution (1-45s) > does not truly reprsent moment to moment brain activity
• unsuitable for those with claustrophobia

Question 4

How does an electroencephalogram work? (EEG)

Answer 4

• measures electrical activity in the brain via electrodes that are fixed to individuals scalp using skull cap
• detects neural activity
• can help diagnose certain conditions e.g. epilepsy

Question 5

What are the strengths of EEG’s?

Answer 5

• high temporal resolution (1-10ms)
• cheaper than fMRI’s
• useful in diagnosis of epilepsy

Question 6

What are the limitation of EEG’s?

Answer 6

• poor spatial resolution, cannot pinpoint exact source of neural activity (general regions)
• lacks precision

Question 7

How do event-related potentials work? (EEP)

Answer 7

• uses electrodes fixed to scalp to detect brain waves
• different to EEG’s, stimulus is presented to participant and researcher looks for activity related to stimulus
  (specific to particular event)

Question 8

What are the strengths of ERP’s?

Answer 8

• good temporal resolution (1-10ms)
• cheaper than fMRI’s
• non-invasive & does not rely on radiation
• can measure brain activity linked to tasks

Question 9

What are the limitations of ERP’s?

Answer 9

• poor spatial resolution
• difficult to control extraneous variables

Question 10

How do Post-mortem examinations work?

Answer 10

• analysis of brain after death
• to determine whether certain observed behaviours during persons lifetime can be linked to structural abnormalities in the brain

Question 11

What are the strengths of post-mortem examinations?

Answer 11

• both Broca and Wernicke relied on post-mortem examinations
• enables deeper regions of the brain to be investigated

Question 12

What are the limitations of Post-mortem examinations?

Answer 12

• ethical issues, consent from individual before death
• can’t investigate brain activity during specific tasks